Add Upsert Value Option on Interaction Mappings

[karamcintyre]

Current State: Interaction Mappings have “Insert Nulls” functionality which allows a null value on Interaction to update a field with a value in it. It also has a “Skip Mapping” multi-select picklist to tell the code to skip a field entirely based on the Interaction Source. However, there is no option to only update a field if it is blank. Currently the only way to handle this is to create a staging field that the Interaction Mapping is mapped to, and use a workflow rule to transfer the value from the staging field to the real field if the real field is blank.

Opportunity to expand: Ideally, it should be possible to determine whether a mapping is updated only if blank based on the Interaction Source, like the way the Skip Mapping multi-select picklist works. The new field could be called "Update Only if Blank" and it could be a multi-select picklist with values matching the Interaction Source values. An admin would indicate which Interaction Sources should only update blank fields for that mapping. This would be very valuable functionality to add to the code, but the method of doing this must be considered carefully, because adding the required complexity to the code could render it unusable by significantly increasing processing times.